Liqtiid-fuel-control system



S.'G. DOWN. LIQUID FUEL CONTRQL SYSTEM.

APPLICATION FILED JULY 5.1919.

MU 5g om m m 1 5 1: Lia m- :7 M i UII P m m r Q MW Emma t m P 3 am a W 13 ml. ,1 u H T. H II [I RE J H 0 30110 m Hi l A m m! 1 UNITED STATES PATENT OFFICE.

SIDNEY G. DOWN, OE BERKELEY, CALIFORNIA, ASSIGNOR TO ASSOCIATED ENGINEER- ING- AND'SUPILY COMPANY, OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF CALIFORNIA.

LIQUID-FUEIi-CONTROL SYSTEM.

Patented Dec. 20, 1921.

Application filed July 5, 1919. Serial No. 308,776.

To all whom it may concern:

Be it known that I, SIDNEY G. DOWN, a citizen of the United States, residing at Berkeley, in the county of Alameda and State of California, have invented new and useful Improvements in Liquid-Fuel-Control Systems, of which the following is a specification.

This invention relates to apparatus employed in connection with a furnace for automatically controlling the supply of liquid, gaseous, or powdered fuel to the furnace, the furnace draft, and the supply of steam or other atomizing medium for atomizing the fuel.

The principal object of my invention is to provide an apparatus of the above character adapted to be controlled by a thermostatic device.

In the accompanying drawing, Figure 1 is a front elevation, partly broken away, of a steam boiler furnace, with my invention applied thereto; Fig. 2 a sectional view of the thermostatic regulating mechanism and Fig. 3 a central sectional view of the fuel controller.

As shown in Fig. 1 of the drawing, my invention is applied to a steam boiler furnace 1 having one or more ash pit doors 2 and one or more stack dampers 3.

In order to illustrate one application of my invention, I have shown a fuel oil burning apparatus, similar to that covered in Patent N 0. 1,314,161 of Carlton D. Stewart, dated August 26, 1919, and comprising a main operating shaft 4, operatively connected by a rod 5 and lever connections to a shaft 6 adapted to operate the stack damper 3 and operatively connected by a rod 7 and lever connections to the ash pit door 2.

At the furnace door 8 there is provided a fuel oil burner 9 and a controller 10 is provided'having valves for supplying fuel oil through pipe 11 to said burner and valves for supplying steam or other atomizing me dium through pipe 12 to the fuel oil burner.

It is not deemed necessary to describe the construction of the controller 10, shown in section in Fig. 3, as the same forms no part of my present invention, except to note that the fuel oil and the atomizing medium valves of the controller 10 are operatively connected to the shaft 4 through a rod 13 and lever connections, so that the flow of fuel oil and atomizing medium is regulated step by step according to the rotative movement imparted to the main shaft 4.

An Oll pump 14 supplies fuel oil under pressure through pipe 15 to the controller 10 and is operated by steam supplied through pipe 16, and steam for atomizing the liquid fuel is also supplied from the pipe 16 to the controller 10.

According to my invention, the main shaft 4 which controls the operation of the stack damper, the ash pit door, and the supply of fuel and atomizing medium to the fuel oil burners, is operated by a thermostatic controlling device comprising a thermostat 17 adapted to be inserted within the steam boiler so as to be subjected to the temperature of the boiler steam and an operating mechanism 18 controlled by the thermostat for operating the main shaft 4.

The operating mechanism 18 may compr1se a casing having two piston chambers 19 and 20 containing pistons 21 and 22 respectively.

The pistons 21 and 22 are connected by the respective piston rods 23 and 24 with a cross head 25, which in turn is operatively connected by a rod 26 and lever connections with the shaft 4.

The space below the pistons 21 and 22 is constantly subject to oil under pressure, as supplied through pipe 27 from the pump 14, while release valves 28 and 29 respectively control the exhaust of liquid from the piston chambers 19 and 20 to an exhaust pipe 30, leading to the fuel oil supply tank 31 of the pump 14.

Springs 32 and 33 tend to hold the respective valves 28 and 29 closed.

The valves 28 and 29 are adapted to be operated by the thermostat 17 through a cross head 34 having hand screws 35 and 36 adapted to engage the respective valve stems CJI If the temperature of the steam in the boiler isat the maximum, the thermostat will operate by the expansion of the rod 39, so as to permit the cross head 34 to assume its uppermost position, in which the valves' 21 and 22 to their lowermost positions, the

shaft t also operates through the rods 5 and 7 to shift the stack damper 3 and the ash pit door 2 to restrict the respective draft openings, so as to provide a draft suitable for the minimum fire.

When the temperature of the steam in the boiler reduces to a predetermined degree, the rod 39 of the thermostat is retracted so as to operate the bell crank lever 38 and thereby depress the stem 37 and the cross head 34.

The screw 36 then acts on the valve stem of valve 29 to open said valve and thus exhaust the oil in piston chamber 20 through exhaust pipe 30.

The piston 22 is thereupon lifted by the pressure of'fuel oil acting below the piston and the rod 23 is raised by the corresponding movement of cross head 25, so that the shaft dis turned a certain amount, such that the rod 13 is actuated to open valves in the controller 10 for increasing the flow of fuel oil and atomizing medium to the fuel oil burner 9, thus increasing the intensity of the fire in the furnace.

The same movement of shaft 4 also operates through the respective rods 5 and 7 to shift the stack damper 3 and the ash pit door 2 to more open positions, so as to adjust the draft to correspond with the increased fire.

If the temperature of the steam in the boiler continues to fall, however, the bell crank lever 38 is moved to a greater extent the contraction of the rod 39 of the thermostat 17, so that the screw 35 engages the valve stem of the valve 28 to open this valve and thereby exhaust fuel oil from the piston chamber 19 to exhaust pipe 30.

The piston 21 is then lifted by the pressure oil below thepiston and the cross head 25 is further operated by the stem 23 so as to cause a further movement of the shaft l. This further movement of shaft t then operates the rod 13 to open valves in troller 10 for increasing the flow of fuel oil and atomizing medium to the oil burner 9, so that the intensity of the furnace fire is correspondingly increased. 1

The movement of shaft 4: also opens the the constack damper 3 and the ash pit door 2 to an piston will move down by gravity. The cross head 25 then actuates the rod 26 to turn the shaft 4-, for closing valves in the controller 10 so as to reduce the fiow of fuel oil and atomizing medium to the oil burner 9 and also move the stack damper 3 and the ash pit door 2 to reduce the draft.

A. further increase in the temperature of the steam will cause the further movement of the bell crank lever 38, so as to permit the valve 29 to close and the piston '22 to be moved, upon equalization of oil pressure on opposite sides, to its lower position.

The shaft 4 isthen turned to a position, in which the valves of the controller 10 are operated through rod 13 to restrict the flow of fuel oil and atomizing medium to that required for a minimum fire, while the stack damper 3 and the ash pit door 2 are further closed to provide a correspondingly reduced draft.

It will now be seen that by the operation of the above described apparatus, the in tensity of the fire in the furnace is controlled step by step through the operation of a thermostat subject to the temperature of the steam in the boiler and the draft is also regulated to correspond with the intensity of the fire; T

Having now described myinvention, what I claim as new, and desire to secure by Letters Patent, is 2- '1. The combination with a steam boiler and furnace, of a controller for regulating the flow of fuel to the furnace,'mechanism for operating said controller including a shaft operatively connected to said controller, a rod operatively connected to said shaft, a

'lating the flow to the burner of liquid fuel and the medium for atomizing the liquid fuel, a rotatable shaft operatively connected to said valves, pistons operatively con nected to saidshaft and normally subject on opposite sides to fluid under pressure, a release valve for controlling the release of lOO fluid under pressure from one side of each piston, a thermostat subject to the heat of the steam in the boiler, and means controlled by said thermostat for successively operating 5 said release valves.

3. The combination with a steam boiler and furnace, of means for regulating the in tensity of the fire in the furnace and the furnace draft, a piston normally subject on opposite sides to fluid pressure and operatively connected to said means, a valve for exhausting fluid under pressure from one side of said piston, and a thermostat, subject to the temperature of the steam in the boiler and operatively connected to said valve.

In testimony whereof I have hereunto set my hand.

SIDNEY G. DOWN. 

